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Nah, I drew a triangle on the map and everything... it took longer and was less precise than using a GPS, but that's not the point now is it!
That's not triangulation.
That's plotting 2 bearings to get 2 position lines and a position. It's navigation but not triangulation.
triangulation definition(in surveying) the tracing and measurement of a series or network of triangles in order to determine the distances and relative positions of points spread over an area, especially by measuring the length of one side of each triangle and deducing its angles and the length of the other two sides by observation from this baseline.
...I don't think I've ever triangulated personally, generally there's only doubt over your position in one dimension (because you're following a path or a ridge) and a single bearing is sufficient to resolve that. CBA with drawing on the map either!
That's not triangulation.That's plotting 2 bearings to get 2 position lines and a position. It's navigation but not triangulation.
Using a map, compass and landmarks to identify your position is not triangulation? That's not what I was taught...
That's plotting 2 bearings to get 2 position lines and a position. It's navigation but not triangulation.
Except it is. Just because somebody else has already measured the distance and angle of one side of the triangle doesn't change that. ransos might not have drawn the accurately surveyed third side of the triangle but it still exists (on the map).
generally there's only doubt over your position in one dimension (because you're following a path or a ridge)
Except when you're not.
From Merriam Webster:
any similar trigonometric operation for finding a position or location by means of bearings from two fixed points a known distance apart
That's what I did, wasn't it? As aracer says, the two landmarks are a known distance apart because they are on the map.
I know it in theory and I've done it, but it's been so long since I've needed to I'd have to look at the map key to work out how far, and which way, to adjust for the grid / mag difference.
Thinking about it, I doubt I've had cause to actually take a bearing this millenium.
[quote="gobuchul"] Awesome....
Except it's not.... it's a pretty basic life skill.
We only had smartphones a decade or so... what exactly did these people do before?
I'm good at memorising the key points on maps because of practice... but its just very basic knowing [b]what [/b]to memorise.. like in St Petersburg knowing I needed to follow a road/river until a bridge then the next landmark being a big onion dome or football stadium etc.
One thing I noticed in India is everyone uses landmarks... even in addresses like "2 streets from the power transformer across the small river towards the hill - number 44"
Think so....
Not had to do it since I was in the Scouts or Army Cadets, so I'd probably struggle on the finer details but I'd be going the right [i]general[/i] direction. Give or take 45° 😀
My 7yo is in Beavers and her mum is volunteering as an assistant leader, so no doubt I'll get some revision in the not too distant future.
Isn't that called a cocked hat rather than triangulation?
That's plotting 2 bearings to get 2 position lines and a position. It's navigation but not triangulation.
YOU are the 3rd point of the triangle.
I can find North using the sun and a wris****ch.... ha HA!*
*Clouds, night time and a digital watch could cause issues....
I can find North using the sun and a wris****ch...
Handy skill but essentially useless in Scotland 😀
Except it's not.... it's a pretty basic life skill.
No it's not. If you intend on being in the middle of nowhere on a regular basis then it is very useful, but for the majority of us it is not useful.
We only had smartphones a decade or so... what exactly did these people do before?
When I rode off-road lots I got all my maps from MTB Magazine - I would just rip it out, go riding and read the instructions if required. Yes we got a bit lost a few times but nothing terminal.
That's plotting 2 bearings to get 2 position lines and a position. It's navigation but not triangulation.
It is triangulation - two points on the map, you're the third one - triangle.
My 7yo is in Beavers and her mum is volunteering as an assistant leader, so no doubt I'll get some revision in the not too distant future.
It will be a while yet, I'm sure they don't do compasses in beavers and I don't think properly in cubs either (at least my lad who is about to leave cubs never has). I certainly first did it with scouts.
Except when you're not.
Extremely rare that you're not following some sort of line feature in circumstances where there is sufficient visibility to take a back bearing. Even if that's something like following a contour line using an altimeter! At some point you might use the compass to provide that line, but in such circumstances I'd probably not be bothered about exactly where I am along it. I'd be surprised if I've not done more nav through trackless terrain than anyone else on here, and actually it's surprising how much you can do without a compass given a good map and sense for terrain (I've used a compass far more for orienteering than anything else, in which case you're certainly not taking traditional bearings - I use a compass without a rotating bezel)
I can use one, but it's hardly surprising if Joe Public generally can't is it? Why would they know how if they have never needed to use one and are never likely to?
That said, I'd like to think that a lot of people could figure out the basics if they messed around with a map and compass for 15 minutes.
I can sort of use a compass. Following a bearing and turning the bezel on the map is fine. But i come unstuck when i get part way down that bearing and find a feature i need to go round. Screws everything up... so i avoid going out if it's crap weather and route is not known or marked.
How do you get better at it? Without trial and error/ involvement of mountain rescue...
Except it's not.... it's a pretty basic life skill.
Is it? Really?
Swimming. First Aid. Yes.
Using a compass? Nah.
My dad taught me when I was young, I also got taught in Geography in school (whether this was part of curriculum or just a good teacher, not sure). I love maps though, always have done always will. Even though I have a GPS I still use map and compass out in the hills as it's better and leads you to explore more. Too many people just follow a plotted red line on a tiny GPS screen and miss the bigger picture.
Cocked hat is when you have three lines from distant points intersecting and since you never get the angles absolutely correct they invariably don't cross at a single point but form a small triangle - the cocked hat.
If you are in mist/cloud/whiteout then you can use the aspect of the slope you are on to get an idea of where you are. I've only ever been "lost" twice in the Lakes, both times in the Fairfield area. The first time I wasn't sure if I was on the Rydal side or the Seat Sandal side of the ridge (dunno how I'd got where I was) - simply knowing that I was on a western slope meant I simply had to contour to the right to find the path down towards Grisedale Hause and Grisedale Tarn.
Yes, it's a basic need for any sail racing or cruising.
I'm not amazed most folks can't use one, not really a requirement to go to the shops is it.
Cubs, scouts then school CCF then yachting. So yes. Also can use a sextant. And have a collection of slide rules including spiral and circular. So why can't I find a hot woman? 😳 😀
No and I can't swim either, I'm stuffed if I'm lost at sea on a boat which then sinks,
I've never used a cocked hat, but have used aspect of the slope a few times. Last time was on beinn dorain in a total white out just to not end up in the wrong valley with a massive walk out
In case anyone is interested:
https://www.ordnancesurvey.co.uk/blog/2015/11/map-reading-skills-how-to-use-a-compass-2/
Yes, it's a basic need for any sail racing or cruising.
Now that I would dispute - I've done plenty of sail racing and never used a compass during one.
Last time was on beinn dorain in a total white out just to not end up in the wrong valley with a massive walk out
Many years ago we cocked up on Beinn Dorain and ended up in the wrong valley with a massive walk out...
aracer - Member
Yes, it's a basic need for any sail racing or cruising.
Now that I would dispute - I've done plenty of sail racing and never used a compass during one.
Dispute it all you like.
Plot me a course to the Canaries from...ohh, Hamble.
Used to know how but I think I'd struggle now. Then again I have no need to do so. Don't do any hill walking and when out on the bike I can normally find my way or ask someone for basic directions.
Bloody Beinn Dorain...
When I was practising my navigation skills, in particular timing distances, I predicted we would reach the summit of Beinn Dorain in 15 minutes, based off where I thought we were (it was misty).
15 minutes later a substantial cairn looms out of the mist and I allow myself a moments smugness, which my companion grudgingly accepts is warranted.
Then the mist lifts and we see the rest of the hill extending beyond. I had successfully navigated us only as far as the Sassenach's cairn, so called because apparently Sassenachs can't navigate in the hills... 😳
[quote=bikebouy ]Dispute it all you like.
Plot me a course to the Canaries from...ohh, Hamble.
I'm sure I could, but it's not really required when going round the cans.
Yes I can
and as a Geologist and I can draw up the maps as well
So, how would [i]you[/i] decide that the line is biased or perhaps where the windward mark is 1nm away in choppy conditions? Or perhaps Championship event RO's give the course vector in..ohh.. hand signals or smoke or maybe shine a light on it.
RTC short course racing is easily done without a compass, if you know the course and where the marks are. Add in an Open Meeting where competitors new to the water are racing and the RO will [i]always[/i] give a compass vector to the windward mark.
You've no need to pick up on anything I've mentioned, I've ran Olympic Qualifiers and all sorts of World Champs as RO. Raced RORC events for the last 25 years (won loads), multiple World Champs in Small and Big boats, including 7 ARC's..
But hey, the RYA Day Skipper onshore course page two outlines what a compass is, and how to use it.
Blah, di..blah.
Yes, I can use one, but in 15 years of proper mountain biking I can honestly say I've never actually had to take a bearing.
Used to do a bit of hiking which required it, as we were always off paths, but no need any more really.
[quote=bikebouy ]You've no need to pick up on anything I've mentioned, I've ran Olympic Qualifiers and all sorts of World Champs as RO. Raced RORC events for the last 25 years (won loads), multiple World Champs in Small and Big boats, including 7 ARC's..
Very impressive, but I've still raced sailing boats without the need for a compass. I could even work out whether the line is biased without one, given it indicates the earth's magnetic field rather than the wind direction (and despite the low level of my races, I was always competitive enough to bother working it out). I think you're making the mistake of thinking that all sail racing is the sort you've been involved with (hint: I've not done a race where the windward mark is 1nm away). Strangely you even mention the sort of racing where you don't need one...
In case you need reminding, this was your original quote:
Yes, it's a basic need for any sail racing or cruising.
Darrell, I reckon none of these big girls blouses could take a dip and strike.
Geology=compass use 7th Dan.
[quote=thestabiliser ]Darrell, I reckon none of these big girls blouses could take a dip and strike.
We're talking about the direction of contour lines and a line perpendicular to that, right? 😉
No. Bedding planes, jointing and faulting. To make a 3D model of structures and artifice.
😉
Hmm, but Google is telling me strike is a contour line!
Oh. GOOGLE. In that case I concede.
Yes. Damn handy skill to have.
Strike is contour line of the rock structure feature, such as bedding plane, which may or may not have anything to do with the contour of the ground profile.
Yep, geology tends to hone compass skills (PhD spent mapping stratigraphy and structures and producing maps of the Atlas mountains), as does cave surveying (miles of new passages surveyed and mapped in the Austrian & German Alps). More recently you might imagine that the past 3 years of orienteering almost every other weekend would have further perfected my compass skills, but to be honest I can now think my way through a landscape. I can't remember the last time I had to take a bearing other than teaching others how to use a compass.
Not blowing my own trumpet, but navigation is probably my strongest life skill by a long shot. 🙂